Search

In this letter a W -band small-size low sidelobe level (SLL) 6 × 16 microwaveguide slot array antenna is proposed based on the silicon micromachining technology. The feeding network within the limited available area consists of several stages of equal T-junctions and TE120-mode-cavity dual-layer power dividers able to build the desired tapering power distribution over a relatively wide bandwidth. The TE120-mode-cavity dual-layer power divider is at the end of the feeding network, which can implement the layer-to-layer transition and the power division simultaneously. Thus, the whole size of the array antenna can be reduced by about 25% compared with the conventional five-stage tree-like feeding network. The overall antenna size is 60 mm × 20 mm × 1.85 mm. The measured maximum gain is 26.1 dBi at 94 GHz, and the corresponding radiation efficiency is 69.2%. The measured SLL in E -plane is below than −18.5 dB within the frequency band from 92 to 96 GHz.

A THz 2-D frequency scanning planar integrated array antenna is developed in this letter. Eight THz leaky-wave antennas are combined with a true-time-delay (TTD) phase-shifting feeding network to steer the beam in two directions by sweeping the frequency. Several H-plane 90° bends with linearly increased length are adopted to achieve the scalable TTD phase shift. The feeding lines are closely spaced to reduce the phase-shifting network occupied area in this progressive phase-shifting scheme. Besides, the E-plane 180° bend is used to construct the double-layer phase-shifting network, maintain the number of multiple scanning sweeps and improve the aperture efficiency. Moreover, in the used microelectromechanical systems (MEMS) fabrication technique, the minimum height of the radiation slot is 0.2 mm, which is too thick and deteriorates the radiating performance. When the double-layer step-profiled radiating slot is used instead of the thick slot, a THz leaky-wave antenna with higher radiation efficiency and better gain flatness can be achieved. Finally, a prototype antenna is fabricated and experimentally validated. The operating frequency range is 325–400 GHz and the beam scanning range is 22.7° × 60° with a maximum radiation gain of 25.28 dBi.

A W-band planar array antenna with high efficiency and wide impedance bandwidth using MEMS micromachining technology is designed and fabricated in this paper. The MEMS fabrication process of selectively etching and gold plating is employed to fabricate the precise structure with the similar property of the hollow waveguide. To satisfy the requirement of maximum thickness, the reduced-height waveguide is applied to design an H-plane equal-amplitude and in-phase power divider with the perturbed and septum structure to enhance its impedance bandwidth. A $\pmb{2}\times \pmb{2}$ -element sub-array is utilized to facilitate the layout of the feeding network in the lower layer. The wide-band-stepped horn is employed as the radiating element. Its simple configuration can guarantee good performance. Finally, an $\mathbf{8}\times \mathbf{8}$ array antenna is fabricated by the MEMS micromachining technology and measured. The total thickness is 2.65 mm, which is less than one free space wavelength. Measurement results indicate that the impedance bandwidth for $\vert \mathbf{S}_{11}\vert is 21.28%. The minimal gain can be up to 23.36 dBi within the whole operating frequency band. Total antenna efficiency is up to 75% covering the range from 86.5 GHz to 104 GHz.